Mineral: Upper-Level WIS Material
Description: Locality: U.S. Western Interior Seaway Displays a 60x view of clear glass-like crystals. These crystals exhibit obvious planar fractures, and what I believe to be "deformation twinning." Note: Existing crystals that are "shocked" by high-pressures during an impact event would be considered as "planar deformation features," or PDF's. However, the sample shown here would be considered as :deformation twinning," A crystal product formed "after" the extreme high-pressure-temperature energy event.

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